The histogram just shows the levels recorded.
I think the writer of the article makes far too much of it.
You need to know what's going on in a scene before you photograph it, not after. It's really of far more use when doing post-processing.
Give me a good light meter any day.

I find it very useful when making a levels adjustment (setting the white and black points) in photoshop, which is usually the second thing I do (after making the image monochrome). I may look it one in-camera to see if any of the highlights are blown, but that's the only other time I use one.

Generally I rely on it often. I feel that it gives me great clues on exposure. I try and avoid flat lines in the shadow or highlight areas. Correction may include metering spot or opening the exposure 1.7 stops. The idea is to visually understand the exposure. More importantly what you want the exposure to do.

It tells me if I should bracket. I rarely look at the histo on the camera or the LCD for that matter. Only when I'm in doubt. In PS it tells me the levels on the chanel mixer when converting to B&W, how far I can push the shadows/highlights, color cast and the list goes on and on.